Targeting the renin-angiotensin signaling pathway in COVID-19: Unanswered questions, opportunities, and challenges.

The role of the renin-angiotensin signaling (RAS) pathway in COVID-19 has received much attention. A central mechanism for COVID-19 pathophysiology has been proposed: imbalance of angiotensin converting enzymes (ACE)1 and ACE2 (ACE2 being the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] virus "receptor") that results in tissue injury from angiotensin II (Ang II)-mediated signaling. This mechanism provides a rationale for multiple therapeutic approaches. In parallel, clinical data from retrospective analysis of COVID-19 cohorts has revealed that ACE inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) may be beneficial in COVID-19. These findings have led to the initiation of clinical trials using approved drugs that target the generation (ACEIs) and actions (ARBs) of Ang II. However, treatment of COVID-19 with ACEIs/ARBs poses several challenges. These include choosing appropriate inclusion and exclusion criteria, dose optimization, risk of adverse effects and drug interactions, and verification of target engagement. Other approaches related to the RAS pathway might be considered, for example, inhalational administration of ACEIs/ARBs (to deliver drugs directly to the lungs) and use of compounds with other actions (e.g., activation of ACE2, agonism of MAS1 receptors, ß-arrestin-based Angiotensin receptor agonists, and administration of soluble ACE2 or ACE2 peptides). Studies with animal models could test such approaches and assess therapeutic benefit. This Perspective highlights questions whose answers could advance RAS-targeting agents as mechanism-driven ways to blunt tissue injury, morbidity, and mortality of COVID-19.

What we have to know about corticosteroids use during Sars-Cov-2 infection.

PURPOSE: Glucocorticoids (GCs), alone or associated to other drugs, were widely used in the management of patients affected by severe acute respiratory syndrome caused by SARS-CoV-2 infection, during the recent COVID-19 outbreak. This review summarizes the available data on HPA axis impairment in GC-treated SARS-CoV-2 patients, focusing on the risk of adrenal insufficiency and on potential drug interactions during concomitant treatments. METHODS: Literature on the impact of GCs therapy on HPA axis and on the consequences of coadministration of GCs and other drugs in SARS-CoV-2 patients has been reviewed. RESULTS: GC treatment can cause symptoms of hypercortisolism, especially in patients with individual hypersensibility, or hypoadrenalism after drug withdrawal, due to hypothalamic-pituitary-adrenal (HPA) axis suppression, with consequences in terms of increased morbidity and mortality risk. On the other hand, in SARS-CoV-2-infected patient's cortisol secretion could be insufficient also due to critical illness-related corticosteroid insufficiency (CIRCI). In addition, in this clinical context, the co-administration of antiretroviral drugs and corticosteroids may trigger drug-drug interaction and enhance the exposure to the latter ones, metabolized through the CYP450 CYP3A pathway, severely impacting on HPA axis. CONCLUSION: Physicians involved in the management of patients affected by COVID-19 should be aware of the need of an appropriate GC dose tapering, and of potential interaction of GCs with antiviral therapy and drugs used to treat associated co-morbidities.

Abnormal laboratory findings and plasma concentration monitoring of lopinavir and ritonavir in COVID-19.

It is not known whether the adverse events (AEs) associated with the administration of lopinavir and ritonavir (LPV/r) in the treatment of COVID-19 are concentration-dependent. In a retrospective study of 65 patients treated with LPV/r and therapeutic drug monitoring (TDM) for severe forms of COVID-19 (median age: 67; males: 41 [63.1%]), 33 (50.8%) displayed a grade ≥2 increase in plasma levels of hepatobiliary markers, lipase and/or triglycerides. A causal relationship between LPV/r and the AE was suspected in 9 of the 65 patients (13.8%). At 400 mg b.i.d., the plasma trough concentrations of LPV/r were high and showed marked interindividual variability (median [interquartile range]: 16,600 [11,430-20,842] ng/ml for lopinavir and 501 [247-891] ng/ml for ritonavir). The trough lopinavir concentration was negatively correlated with body mass index, while the trough ritonavir concentration was positively correlated with age and negatively correlated with prothrombin activity. However, the occurrence of abnormal laboratory values was not associated with higher trough plasma concentrations of LPV/r. Further studies will be needed to determine the value of TDM in LPV/r-treated patients with COVID-19.